A minor key has a relative major.
Thus to play in Dm you are essentially playing
in F.
If you have a natural C you have a D natural minor and
with a C# (need for the the V7), then you have D
harmonic minor.
Either one could occur.
When you have a pure minor chord then you might have a #7.
Then you'll end up with a melodic minor.
However, is it really a melodic minor or just a #7 tension?
The real key is whether there is a natural 6 degree.
If there is no natural 6 then its just a minor chord with
a #7 and still no melodic minor scale.
reed
Reed Kotler
reed@justjazz.com
http://www.justjazz.com